Comparison of volume gain AMPs
Why is the "volume" expressed in dBV
Why is the "volume" expressed in dBV When you compare amplifiers by loudness, the voltage value, expressed in dBV, should be used. The difference in voltage will show the difference in decibel (dB) between the amplifiers.
The power values in regular mW do not convenient to direct comparison.
The direct comparison by power is only suitable for speaker amplifiers operating with an ultra-low-ohm load. This does not apply to headphone amplifiers where the headphone resistance is higher than 8-16 ohms.
Because of the higher resistance of the headphones, when compare the volume of a musical signal it is necessary to simultaneously take into account the current and voltage limits. The speaker amplifier have limit by current. For the exact difference between the amplifiers in decibel, the power value must be converted into voltage in units of dBV, taking into account the margin by current for the music signal to 12 dB.
If made a comparison simply by power, then the error will reach up to 12 dB. When sorting by volume, you can see that at the same volume values in dBV, the power values in mW will be different.
What and how to compare with the characteristics provided by manufacturers
The value of the high quality mode power is equivalent to class A. Typically, manufacturers for this power indicate the percentage of distortion, which should be no more than 1%.
Simply the Maximum power, this is the power level above, which the amplifier is already "wheezing" or the volume control is already at its maximum level. Usually indicated without a percentage of distortion, because high quality for this volume level is not implied.
Определить напряжение в dBV по данным производителей можно в специальном калькуляторе (в разработке)
Выходная мощность и сопротивление наушников
Так как мощность зависит от тока, напряжения и сопротивления усилителя, то для разных сопротивлений наушников будут лидировать разные усилители. По умолчанию предлагаются сопротивления 32 и 300 Ом. Можно задать любые другие значения.
Самый громкий - самый лучший?
Если выбрать излишне громкий усилитель, то можно столкнуться с проблемами фонового шума и/или несовершенства регулятора громкости. Усилитель стоит подбирать под чувствительность используемых наушников.
